Unravel the Spinodal Decomposition Kinetics in(FeCoCrNi)85(AlCu)15 Alloy through Small-Angle Neutron Scattering  

作　　者：Shun-Fu Xie Han-Qiu Jiang Zhen-Hua Xie Wei-Wen Zhang Yu-Bin Ke 

机构地区：[1]School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou,510641,China [2]Spallation Neutron Source Science Center,Dongguan,523803,China [3]Institute of High Energy Physics,Chinese Academy of Sciences,Beijing,100049,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2025年第1期86-92,共7页金属学报(英文版)

基　　金：financially supported by the National Key Research and Development Program of China(Grant No.2021YFA1600701);the Guangdong Basic and Applied Basic Research Foundation,China(Project No.2021B1515140028);the National Natural Science Foundation of China(Grant No.12275154)。

摘　　要：High entropy alloys(HEAs)constituted of single solid solution phase,but remains chemical inhomogeneity in nature due to its multi-principal composition.Currently,existence of nanoscale spinodal decomposition(SD)phase in matrix was found to have significant impact on the properties of HEAs.Nevertheless,the morphology evolution and the kinetics of SD is not clear,which hinders in-depth understanding of the structure-property relationship.In this study,we examine the spinodal structures in(FeCoCrNi)85(AlCu)15 HEAs at different states using in-situ small-angle neutron scattering(SANS),in conjunction with transmission electron microscopy technique.The result demonstrates that SD occurred when aging the HEA samples at temperatures ranging from 500 to 800℃,which leads to the phase constitution of NiAlCu-rich and FeCoCr-rich spinodal phases,L1_(2)ordered phases,and FCC matrix.The characteristic wavelength of SD(λ_(SD))grows from 5.31 to 51.26 nm when aging temperature rises from 500 to 800℃,which explains the enhancement of the alloy’s microhardness.The SD kinetics was unraveled by fitting the time-dependentλ_(SD)through in-situ SANS measurement at 700℃.During isothermal treatment at 700℃,theλ_(SD)increases from 10.42 to 17.43 nm with prolonged time,and SD is in the late stage from the exponential trend of theλ_(SD)over time.Moreover,comparing with aging temperature,the aging time has a relatively minor impact on the coarsening of SD.

关 键 词：High entropy alloys Spinodal decomposition Small-angle neutron scattering KINETICS 

分 类 号：TG139.8[一般工业技术—材料科学与工程]